1. Field of the Invention
This invention generally relates to a bicycle rim brake assembly. More specifically, the present invention relates to a bicycle rim brake assembly configured to apply a braking force to a rim of a wheel of a bicycle.
2. Background Information
Bicycling is becoming an increasingly more popular form of recreation as well as a means of transportation. Moreover, bicycling has become a very popular competitive sport for both amateurs and professionals. Whether the bicycle is used for recreation, transportation or competition, the bicycle industry is constantly improving the various components of the bicycle. One component that has been extensively redesigned is the bicycle brake assembly.
One well-known example of a bicycle rim brake assembly is the caliper brake. A caliper brake is configured to apply a braking force to the wheel of a bicycle by pinching the rim of the wheel with a pair of brake shoes attached to a pair of brake arms. Caliper brakes are designed such that the position of the brake shoes can be adjusted up and down so that the brake shoes contact appropriate surfaces on the rim. In a conventional caliper brake, a vertically elongated oblong hole is provided in each brake arm and a bolt for fastening the brake shoe is inserted through each oblong hole. With this conventional design, the process of adjusting the vertical positions of the two brake shoes is troublesome because the vertical position of each of the two brake shoes must be adjusted separately.
Another example of a bicycle rim brake assembly is a center pull caliper brakes that includes a fastening arm that supports the brake arms on a bicycle such that brake arms freely pivot on the fastening arm. In such a conventional design (e.g., Japanese Laid-Open Utility Model Publication No. 55-56795) the fastening member is vertically adjusted to align the brake shoes vertically with the bicycle tire rim. The fastening arm has an outer anchoring part configured to secure the outer casing of a brake cable and pivotal support parts configured to support both brake arms in a freely pivotal manner. A vertically elongated oblong hole is formed in the fastening arm. A bolt for fastening the brake device to the frame is inserted through the elongated hole and fastened to the frame of the bicycle. The vertical positions of the brake shoes are adjusted by adjusting the mounting position of the fastening arm, thereby adjusting the vertical position of the entire brake assembly. Thus, with this conventional design, the process of adjusting the vertical positions of the brake shoes is simplified because a fastening arm that is separate from the brake arms is provided and the vertical positions of both brake shoes can be adjusted simultaneously by adjusting the position of the fastening arm. Additionally, since the position of the pivotal center of the brake arms does not change relative to the positions of the brake shoes, the braking ratio of the two brake arms of the brake device does not change.
With the conventional center pull caliper brake described above, the process of changing the vertical positions of the brake shoes is simplified because the existence of the fastening arm enables the vertical positions of both brake shoes to be adjusted by moving the entire brake device up and down. However, the fastening arm has a complex structure that includes the outer anchoring part (which secures the outer casing of the brake cable), two left and right pivotal support parts (which support the brake arms in mirror image positions in a freely pivotal manner), and the elongated oblong hole for adjusting the vertical position. In short, since the conventional design requires a fastening arm having a complex structure to be provided in order to adjust the vertical positions of the brake shoes more easily, the structure of the entire brake device is also more complex.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved bicycle rim brake. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.